Genome-Wide Identification and Characterization of the C2H2 Zinc Finger Gene Family in Pear (Pyrus bretschneideri) and Its Potential Role in Drought Stress Response

C2H2-type zinc finger transcription factors play crucial roles in regulating plant growth and responses to abiotic stresses. Although pear is an economically important fruit crop with available genomic resources, the comprehensive analyses of its C2H2 gene family remain limited. In this study, we performed a genome-wide identification of C2H2 genes in pear, identifying 52 members that were unevenly distributed across 17 chromosomes. The predicted PyC2H2 proteins ranged from 343 to 1764 amino acids in length, with molecular weights between 12.4 and 62.7 kDa. Phylogenetic analysis classified these 52 PyC2H2 proteins into 10 classical clades, where genes with closer evolutionary relationships shared more similar conserved motifs. Collinearity analysis identified 37 collinear gene pairs between Arabidopsis thaliana and pear, suggesting evolutionary conservation. Promoter analysis revealed the presence of various cis-acting elements associated with hormone and stress responses, including Box 4, G-box, and GT1-motif. Additionally, the expression patterns of PyC2H2 genes differed among pear organs. These results provide valuable insights into the potential roles of PyC2H2 genes in drought stress responses and offer a foundation for future molecular breeding of drought-tolerant pear cultivars.